The present invention relates to an inkjet head, and in particular, to a structure of a manifold for connecting an ink supply route to a head chip on which a nozzle for jetting ink is formed.
On an inkjet head installed on an inkjet printer, there is provided a head chip on which an ink-jetting nozzle is formed. This head chip includes one on which singular or plural nozzle rows each having plural nozzles which are open in the same direction to form a line in one direction, are formed. A head is fixed on a carriage of a printer main body to be installed thereon. On the head chip, there is provided an actuator element such as a piezoelectric element that gives the jetting force to a nozzle.
As is used in the inkjet head described in Patent Document 1, a manifold representing a component for connecting an ink supply route to a head chip is used. As a manifold, resin molded components are preferably used.
On the outer surface of the head chip, there is formed an ink supply port that is communicated with a nozzle to be open. On the manifold, there are formed a channel connection port and a groove that is communicated with the channel connection port. When the groove on the manifold is applied to the ink supply port, and an ink supply pipe is connected to the channel connection port on the manifold, the manifold connects the ink supply route to the head chip.
(Patent Document 1) TOKKAI No. 2004-090494
The channel on the manifold needs to be designed in accordance with ink characteristics such as ink discharge and ink viscosity in the course of recording operations. Heretofore, the manifold has been made in full measure for each channel characteristic required for the manifold. For example, even in the case of new requirements to enlarge or to downsize a cross-sectional area of a channel, there has been designed and manufactured a manifold whose cross-sectional area of a channel is enlarged or downsized, to be used. Therefore, there have been occasions wherein a manifold is redesigned each time ink is changed, for example, and a manifold is redesigned for changing ink discharge even in the same ink.
Meanwhile, there is sometimes an occasion wherein jetting characteristics of a nozzle are affected by heat that is generated by driving of a head chip and is filled therein. If heat is maldistributed in the head chip, jetting characteristic of a nozzle varies depending on a position of the nozzle, and its performance is affected. Heat maldistributed in the head chip is diffused through ink filled in the manifold, and is made uniform.
However, the smaller the cross-sectional area of a channel of the manifold is made, the more serious the problem of unevenness of heat generated in the head chip is, and jetting characteristics between nozzles in the head are fluctuated by distribution of ink temperature.